SRBs

Come with almost no moving parts, very little complex plumbing. It was relatively easy to refurbish them rather than a liquid-fuelled stage. I think the Shuttle is the only liquid fuelled rocket which has been reused and the engines there didn't have the indignity of ending up in the North Atlantic.

The Soviets were going to reuse the four strap-on liquid-fuelled boosters for the Energia rocket; AFAIK it was not done for either the Polyus or Buran launches and the boosters would eventually be redesigned into the disposable Zenit launcher.

Top one

Colour me sceptical

This is a very small formation and they are claiming to have found a reserve 2/3 the size of the colossal Groningen gas field, more than 30 times as large as the Morecambe Bay fields and 10 times the size of *all* the reserves remaining in the UK sector of the North Sea. In each of these cases the reserves are known only by drilling a large number of widely dispersed wells into well-understood formations and long term monitoring. That's not possible here.

What's more, if they got a 20% recovery rate from this field they'd pull up very nearly half as much gas as the USGS reckons is economically recoverable from the *whole* Marcellus Formation in the Eastern United States which is almost the size of England.

I think a lot more work needs to be done before anyone thinks that Blackpool is sitting on a gas fortune. But in the meantime I bet that 200 trillion number is doing wonders for their share price.

Satellites are harder to predict

The exact time the satellite begins its reentry depends on many factors, but mostly the density of the atmosphere where it is orbiting. Because of heating from solar radiation the atmosphere's density changes over periods of hours and days which can dramatically change the amount of drag being experienced by the satellite.

Added to which this satellite has probably lost all attitude control so it will be tumbling and experiencing variable amounts of drag, all of which make predictions a bit less - well - predictable.

An asteroid on the other hand approaches the Earth through a vacuum at a relative speed of several to tens of kilometres per second following the laws of Mr. Newton. The atmosphere only has any effect on it during the last few seconds before it carves out a dent on the surface.

I suppose we should be glad that there are no economic uses for pure and applied mathematics or fluid dynamics. I mean apart from the uses that underpin many of the high value industries we supposedly need to grow the economy.

Nope definitely a solar orbit

Snoopy's ascent engine was reignited after being let loose from Charlie Brown and allowed to burn until empty. This let NASA test that the engine could be restarted in an emergency. There was enough thrust to inject it into a solar orbit. Had it been put into a lunar orbit it would have crashed by now because of the Moon's irregular gravitational field.

Make it Scratch

A great little language, easy to pick up, it produces great results in very little time for the attention starved youth of today, you can create multimedia projects and games, share them with people on almost all hardware platforms and you get to learn the fundamentals of program design as well as event-driven, multi-threaded programming.

The biggest problem with Scratch is getting kids to stop playing with it.

That and his ability to survive

Every day that goes by and the question 'why is Steve Ballmer still in charge of Microsoft?' goes unanswered. He's unconvincing as a tech guru, a lousy salesman for the good stuff Microsoft does produce and the company appears to be stagnant.

Time to put a visionary in the public light over at Redmond and get people excited about the very cool stuff Microsoft is developing in its labs.

A use for Twitter?

During the recent riots, the local police force ran an excellent Twitter feed giving up-to-the-minute information about the local situation. I know who live on their own or who are otherwise vulnerable who felt reassured there was timely official news that contrasted with the scary rumours flying around on other social networks.

Cutting that feed off could have made things worse for a lot of people who otherwise didn't have information about what was going on.

But it didn't

Section 28 wasn't there to stop the promotion of homosexuality (whatever that means). It was there to stop any discussion of the subject. It was a hateful piece of legislation imposed to assuage a particular narrow-minded part of the population at the expense of a vulnerable minority.

Dear god no!

Plenty

Thorium isn't a nuclear fuel. It's fertile.

You transmute Th-232 into fissile U-233 inside a fission reactor.

You then require the economically dubious process of reprocessing to separate U-233 from Th-232 and fission products. Which produces huge amounts of actinide waste that has to be disposed of - hopefully not by pouring it into the Irish Sea.

U-233 makes for fabulous bombs. Don't we have rather too many nuclear weapons states as it is?

So nothing at all to do with weapons then?

The bit about NIF that gets a lot less attention is that it is also used to simulate the conditions inside a nuclear weapon at the moment fusion is triggered. Ever since the test ban treaty the bomb people haven't been able to turn chunks of Nevada glow-in-the-dark, so they've had to resort to simulations. And since the UK is joined at the hip to American warhead design, we've got an interest in this project.

"NIF is crucial to the NNSA Stockpile Stewardship Program because it will be able to create the extreme conditions of temperature and pressure that exist on Earth only in exploding nuclear weapons and that are therefore relevant to understanding the operation of our modern nuclear weapons."

Radio dating

You're right about using radioactive decay of isotopes to perform dating, but where it falls down is that there aren't any isotopes of gold with half lives long enough to perform geological dating. So you have to make an assumption that the gold was present when the rock was formed (in the case of Isua when sediments were metamorphosed into gneiss) and use the radiodate established from other elements in the rock - IIRC the Isua was dated using rubidium strontium dating.

Lifetime costs for nuclear?

Do the costs in that document include the cost of decommissioning the UK's nuclear power stations? The taxpayer has been repeatedly stung by ever-escalating prices for scrapping the Magnox plants (they couldn't privatise nuclear and get the private sector to take on decommissioning costs) and making the spent fuel safe. It's running at something over $2 billion a year already and will only increase as the AGRs begin to reach the ends of their lives.

Close but no cigar

Although the 'too cheap to meter' quote is often ascribed to Lord Marshall of the CEGB, it actually comes from Lewis Strauss of the US Atomic Energy Commission and he was talking about nuclear fusion not fission.

The full quote is:

"Our children will enjoy in their homes electrical energy too cheap to meter... It is not too much to expect that our children will know of great periodic regional famines in the world only as matters of history, will travel effortlessly over the seas and under them and through the air with a minimum of danger and at great speeds, and will experience a lifespan far longer than ours, as disease yields and man comes to understand what causes him to age."

How goes the invisible shed?

You're in fine company Lester

Please don't feel down because NAOMI didn't rise to the occasion; even the mighty NASA has had its share of failures to launch.

In fact you've actually beaten NASA. In 1960, Mercury Redstone I only made it 10cm from the pad before something horribly expensive went sproing! shut down the engines and brought the rocket gently back down to the Earth.

So by my calculations if you keep up this rate of success you should be on the Moon round about 2020.

Two reasons

In part it's a technology demonstrator that solar power can be used for deep space missions with low pier requirements, but in part it's been forced on the US by a lack of Pu-238 to go into radio thermal generators. The US has very limited supplies of the isotope which have to be shared between NASA and the military, and in recent years the US has been buying supplies from Russia. The US is ramping up production again, so this might only be a temporary bottleneck.

$500 000?

Sad news

I had the good fortune to be given a guided tour by Tony last year and his enthusiasm for every aspect of the Museum was evident and infectious. His a huge loss and my sympathies go to his friends and family.

Space Race

The Americans pulled decisively ahead of the USSR during the Gemini missions when the Soviet programme was effectively grounded. Their Voskhod manned capsules were death traps and the Soyuz programme was well behind schedule and of very poor quality - let's not forget Soyuz 1 killed its pilot.

Gemini on the other hand showed the Americans could manoeuvre freely in space, conduct long duration missions and repeatedly perform rendezvous - something the Soviets did not master until much later. At the same time the Americans had perfected large rocket engines and were able to get their bigger, heavier Saturn V off the pad with just five engines compared to the N1's 30 - which unsurprisingly, didn't work well.

Where the Soviets did score was that when they finally debugged their simple designs they proved exceptionally reliable - it's not poverty that's kept them using the Soyuz and Proton boosters - it's because they've had an epic success with them. And the Soviets did perhaps produce the best main engine ever designed for the N1 - used individually or in pairs it's been a huge success on the Atlas V.

Nonsense

They're coming from Denmark, compared to Danish the whole 'Bork! put de chicken in de pot! Bork!' dialect of Southern Sweden will be a breeze.

BTW. There's a sense of justice to all this. Now the Swedes are finding out what it was like to be English a thousand years ago - living in constant fear of an invasion from the sea of ferocious Scandinavian hairy rabid killers.

I'm pretty sure Bangor is fireproof

Viagra ads

The little blue pills don't really need marketing, but there does seem to be a lot of ads for erectile dysfunction on telly of late (usually during action movies - make of that what you will). They obviously can't show the condition or any before and after photos, so they have to approach the matter in incredibly elliptical manners. Watch one with the sound muted before the info at the end and there is precisely zero chance you'd guess what it was advertising - debt problems? soft furnishings? bedside lighting? a particularly dull holiday park?